Arc welding



J1me 1934- s. SANDELOWSKY ET AL 1,963,363

ARC WELDING Inventors. Sally Sandelowskg, Kori Belling, bg Their Attorney.

Filed March 21. 1932 Patented June 19, 1934 v UNITED STATES PATENT OFFICE Aao WELDING Sally Sandelowsky, Hennigsdorf, and Karl Belling, Berlin, Germany, assignors to GengalkElectric Company, acorporation of New Application March 21, 1932, Serial No. 600,340 In Germany March 26, 1931 7 Claims. (Cl. 219-8) Our invention relates to arc welding and more gization increases and decreases with an increase particularly to apparatus for automatically peror decrease in the length of the welding arc. The forming arc welding operations. energization of the electromagnet may be con- It is an object of our invention to provide imtrolled in accordance with any characteristic of proved'means for rotating the welding electrode the welding circuit, but is preferably controlled and simultaneously feeding it toward the work in accordance with the current or voltage thereof. at a proper rate of speed to maintain during the The electromagnet may be connected directly in welding operation a welding arc of proper length the welding circuit, or its energization may be and voltage. controlled by means associated with the welding It is a further object of our invention to comcircuit. Such arrangements are old in the art bine with our improved feeding mechanism and constitute no part of our present invention. means for magnetically controlling the welding Current is supplied to the electrode near its arc to steady it and prevent it from being dearcing terminal through a hollow sleeve 14 which flected or blown out during the welding operais connected to one terminal of a source of supply tion. Our improved magnetic control forms the through conductors 15 and 16. Conductor 16 is subject matter of our divisional application, Sepreferably formed in a spiral which encloses rial No. 700,130,1iled November 28, 1933, for Arc sleeve 14 and tapers in a direction away from welding. the arcing terminal of the electrode. The flow Further objects of our invention will become of current through this spiral conductor generapparent from a consideration of the following ates a powerful electric field which increases in specification describing two embodiments thereof strength upwardly, due to its conical arrangeillustrated in Figs. -1 and 2 of the accompanyment. Sleeve 14 is preferably made of maging drawing. netic material in order to concentrate the flux In the drawing Fig. 1 is a view partly in secabout the electrode. This flux has a steadying tion of a welding head embodying our improved effect on the welding arc and prevents it from so feeding mechanism, improved magnetic control, being deflected or blown out during the welding and means for cooling the same and protecting it operation.

from the action of the welding arc, and Fig. 2 Sleeve 14 and conductor 16 are preferably made is a fragmentary view of a welding head such as hollow and cooled by circulating therethrough 30 illustrated in Fig. 1 showing a modified feeding a suitablecooling medium such as water. A

mechanism in accordance with our invention. water jacket 18 is also interposed between the Referring to Fig. 1 the electrode 1 which, is welding arc and the feeding mechanism in order preferably a carbon electrode or an electrode of to protect it from the heat of the arc. The coolthe non-consuming type, is supported in a hollow ing medium is supplied through pipe.19, conducscrew 2 hereinafter referred to as a spindle. It is tor 16, sleeve 14, pipe-20 and jacket 18 from which clamped in the spindle by means of a nut 3, alit is discharged through a pipe 21. This cooling though other means may be provided for attachpermits a compact arrangement of parts being ing it thereto. The spindle is rotated by an elecemployed as well as the location of spiral conductric motor. 4 with which it is mechanically contor 16 and sleeve 14 very close to the arcing ter- 40 nected through gears 5 and 6. The connection minal of the electrode. a between gear 6 and the spindle is obtained Additional material may be added to the seam through a groove and key 7 so that the spindle during welding by supplying thereto a welding is free to move through the gear but is held wire 23 which may be automatically fed into the against rotation relative thereto. Supported on are through a nozzle 24 by means of a feeding and normally rotating with the spindle is an inmechanism (not shown). Preferably, the nozzle ternal screw 9 hereinafter referred to as a nut. 24 and the welding wire 23 are electrically insu- This nut is supported in a housing 10 by means lated from the welding head and from the rest of a ball bearing 11. This housing also serves to of the machine frame in order to prevent the arc enclose gears 5 and 6 and acts as a support for from striking over to the welding wire and form- 50 an electromagnet 12 which may, as illustrated in ing an are between the welding wire and the electhe figure,'be formed integral therewith. Nut 9 trode. is provided with a disklike portion 13 located. The mechanism above described operates as opposite to and constituting an armature for an follows: An arc is established between the elecelectromagnet which is energized in accordance trode 1 and the work 17 by means of a piece of 6 with a characteristic of the are so that its enercarbon or the like. If the arc is of the proper length, the electromagnet 12 will not act on the armature 13 of the nut 9 and no feeding action will be obtained. The electrode, however, will be rotated at a constant rate of speed'by the motor 4 and the.arc at the terminal of the electrode will be stabilized by this rotation and by the magnetic influence of the fleld generated by the welding current flowing through spiral coil 16. If the arc length becomes too great the electromagnet 12 will be energized attracting thereto armature 13 of the nut 9 and holding it against rotation. With the nut 9 thus prevented from rotating, the spindle 2 is fed therethrough by reason of the threaded engagement of these two members. As soon as the arc length attains a normal value, the electromagnet 12 will be deenergized, again permitting nut 9 to rotate with spindle 2 and thus preventing further feeding of the electrode toward the work. It is of course apparent that rotation of the nut 9 need not be arrested since a feeding action may be obtained if its rate of rotation be decreased relative to the rate of rotation of spindle 2. Consequently, the braking effect of the magnet 12 on the disk 13 before these two members are brought into engagement will be effective and may be used for feeding the electrode toward the work.

By suitably modifying the arrangement shown in Fig. 1 means may be provided for feeding the electrode into engagement with the work and thereafter withdrawing it to strike an are after which a proper feeding of the electrode toward the work is obtained for maintaining the welding are at its desired operating value. Such an arrangement is shown in the modification illustrated in Fig. 2. In this figure parts corresponding in function to those in Fig. 1 have been designated by like reference numbers. An additional rotating magnet 25 is employed in the arrangement'illustrated in Fig. 2. Current is supplied to the winding of this electromagnet through slip rings 26 which are connected through conductors 2'1 to a suitable source of supply. The winding of magnet 12 is connected to a suitable source of supply through conductors 28. As in Fig. 1 magnet 12 is stationary but magnet 25 is rotated in the same direction as spindle 2 but at a higher rate of speed through gears 29 and 30. Gear 29 is supported on the same shaft as gear 5 and simultaneously driven therewith by motor 4 which may be supported on the housing 10 as illustrated. By any suitable means responsive to a characteristic of the welding circuit, such as arc length and voltage, electromagnet 12 is energized when the arc is too long and electromagnet 25 energized when the arc is too short.

The operation of the arrangement illustrated in Fig. 2 is as follows: Upon completing the welding circuit magnet 12 will be energized due to the high voltage between the electrode and the work. The energlzation of magnet 12 will arrest the rotation of nut 9 and occasion a feeding motion of electrode 1 and spindle 2 toward the work. When the electrode engages the work, electromagnet 12 will be deenerized and electromagnet 25 energized. Upon the energization of electromagnet 25 a reverse feeding operation is obtained until an arc length of normal voltage is established. Thereafter, the electromagnet 12 is periodically energized in order to feed the electrode toward the work and compensate for its consumption in the arc. Should ,an obstruction be encountered during the welding operation the arrangement just described will operate to withdraw the electrode a sufficient amount to traverse this obstacle at the same time maintaining the welding are at proper length and voltage. Consequently, the arrangement shown in Fig. 2 is particularly suitable for welding irregular seams.

While we have shown and described two particular embodiments of our invention, it is apparent that various modifications and variations may be made without departing from the spirit and scope thereof. For example, the construction and arrangement of the electromagnets may be different from that illustrated and both of these magnets in an arrangement such as shown in Fig. 2 may be rotated in order to accomplish a proper feeding of the electrode. It is also apparent that in place of non-consuming electrodes for which the apparatus is particularly suited,

consuming electrodes may be used without departing from our invention. It is also apparent that either the internal screw or the external screw may be positively rotated and the rotation of the remaining screw controlled in order to control the feeding of the welding electrode.

What we desire to secure by Letters Patent of the United States is:- 1. Are welding apparatus comprising an internal screw and an external screw one of which is supported on the other and normally rotated therewith, means for-rotating one of said screws, means for attaching an electrode to said screw, and means responsive to a characteristic of the welding are for controlling the rotation of said other screw.

2. Arc welding apparatus comprising an externally threaded spindle, means for supporting an electrode on said spindle, means for rotating said spindle, a nut for said spindle supported thereon and normally rotated therewith, and means responsive to a characteristic of the welding are for controlling the rotation of saidnut.

3. Welding apparatus comprising an electrode holder having a threaded spindle, means for rotating said spindle, and nut threaded on said spindle and rotatable therewith, and means responsive to a characteristic of the welding are for controlling the rotation of said nut and the rate of feed of said electrode.

4. Arc welding apparatus comprising a hollow externally threaded spindle, means for support ing an electrode in said spindle, means for rotating said spindle, a nut for said spindle supported thereon and normally rotated therewith, means including anelectromagnet for controlling the rotation of said nut, and means for controlling the energization of said electromagnet in re sponse to a characteristic of the welding arc.

5. Arc welding apparatus comprising a stationary annular electromagnet, a hollow externally threaded spindle extending through said electromagnet, means iorsupporting an electrode in said spindle, means for rotating said spindle, a nut supported on said spindle and normally rotated therewith having a portion thereof constituting an armature for said electromagnet movable into engagement therewith by the energization of said electromagnet, and means responsive to'a characteristic of the welding are for controlling the energization of said electromagnet and the rotation of said nut.

6. Arc welding apparatus comprising a plurality of relatively rotating annular electromagnets, an externally threaded spindle extending through said electromagnets, means for supporting an electrode on said spindle, mews for rotating said spindle, a nut supported on said spindle and normally rotated therewith having a portion screw supported on and normally rotating with said rotating screw, means for rotating said electromagnets relative to one another, an armature for said electromagnets located between said electromagnets and movable.into engagement with one or the other thereof when attracted thereto by the energization of said electromagnets, means for attaching'said armature to the screw supported on and normally rotated with said rotating screw, and means responsive to a characteristic of the welding are for controlling the energization of said electromagnets.

SALLY SANDELOWSKY.

KARL BEIJING. 

